The equation of director circle of the hyperbola −x2a2+y2b2=1, if b>a, is
The combined equation of the asymptotes of the hyperbola x2a2−y2b2=1is x2a2−y2b2=−1..
The locus of the point of intersection of perpendicular tangents to the circles x2+y2=a2 and x2+y2=b2 is